global-equity-indices

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the absent annotations, the description discloses data source (Yahoo Finance), cost ($0.010/call), and no API key requirement. It also details the output (level, % change, range context, region posture), offering good behavioral transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences long, front-loaded with the main purpose, and every sentence adds value (indices list, output details, source/cost). No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (one optional param, no output schema, no annotations), the description covers all essential aspects: indices, data fields, region posture, data source, cost, and use case. It is complete for an agent to understand and invoke.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 100% schema description coverage for the single parameter 'regions,' the schema already explains its purpose. The description adds minimal extra meaning by implying regions correlate to the listed indices, but doesn't specify valid values or format, so baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool provides a 'Global equity snapshot' of 9 major indices plus DXY, with specific data points like current level, daily % change, and region posture. This verb+resource combination distinguishes it from sibling tools like 'equity-brief' or 'stock-price-multi' by its explicit index focus.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description mentions 'Overnight context for global macro agents and forex positioning,' providing clear context for when to use. However, it does not explicitly state when not to use or list alternatives, so it misses the top score.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.